Steam-superheater.



G J. GHURGHWARD, G.H. BURROWS & C. G. CHAMPENEY.

STEAM SUPBRHEATER.

APPLICATION FILED DEO.3. 1909. 946 9,088. Patented Aug. so; 1910.

2 SHEETS-SHEET 1.

G. J. UHURGHWARD, G. H. BURROWS & C. G. CHAMPENE'Y. STEAM. SUPERHBATER. APPLIoATIoI FILED DEo.a,19o9.

969,088. Patented Aug. 30, 1910; v 2 Simms-SHEET 2.

NTFD STATES PATENT FFICE.

GEORGE J. CHURCHWARD, GEORGE H. BRROWS, .AND ClIiIFEOl-ll)lC.A CAMPENEY, 0F SWINDON, ENGLAND.

STEAM-SUPERHEATER.

ananas.

Y Specification of Letters Patent. Patented Aug, 30, 19410 Application filed December 3, 1909. Serial No. 531,145.

Toull whom it may concern.:

Be it known that we, Grenen J. CHURCH- wAnD, GEORGE H. BUnnows, and CLIFFORD C. CHAMPENEY, subjects of the King of Great Britain and Ireland, residing in Swindon, in the` county of Vililts, England, have invented a certain new and useful lmprovement in Steam-Superheaters, of which the following is a true and exact description, reference being hadvto the accompanying drawings, which form a partthereof.

The present invention relates to steam superheating appliances for tubular boilers especially those of the locomotive type.

More particularly the invention relates to superheaters of the general class or type known as flue tube superheaters in which the tubes within which the steam is superheated are located within enlarged iiue tubes of a tubular steam boiler and provide chaunels through which steam passes from the steam space proper of the boiler to the tube or tubes through which it isdelivered after being superheated to the engine cylinder or cylinders.

One main object of the invention is the production of a superheater of the kind specified which is simpler in form and more etlicient in operation than those heretofore used and is so constructed and arranged at the smoke box end of the boiler as to give improved facility for cleaning the superheating tubes' and the flues in which .they are inserted. Y

A further objectv of the invention is to provide a construction characterized by the ease and simplicity with which agroup of superheating tubes may be removed from the iue'tube in which they are inserted without. disturbing the groups of superheating tubes inserted in other flue tubes. v

A- further objectof the invention is the provision of a simple and eective arrangementfor keeping the velocity of the steam as nearly constant as possible in its passage through the superheater and in particular to insure substantially uniform distribution of the stream of steam through the various superheating tubes. V

A further object of the invention is the provision of a structure in which the main Superheating header or headers may be. made shortI in depth, this we obtain lo" arranging each main header between rows of enlarged flue tubes and providing superheating conneXed to and forming nections to the header which lie some above yand some below the header and enter the corresponding pair of rows of enlarged flue tubes. l

The various features of novelty which characterize the present invention are pointed out with particularity in the claims ana part of this specitication.' For a better understanding of the invention, however, and the advantages possessed by it, reference should be had to the accompanyingl drawings and descriptive matter in which we have illustrated and described forms of apparatus embodying the invention. I

Of the drawings, Figure 1 is a sectional elevation of a portion of a boiler provided with our improved superheating appliances. Fig. 2 is a partial end elevation of the boiler proper of F 1 with the smoke box wall in section. Fig. 3 is a side elevationg' Fig. 4 a plan -view, and Fig. 5 an end lelevation of the main steam header employed. Figs.

6 and 7 are sections through the mainheader on lines 6 6 and 7 7 respectively, of Fig. 3. Fig.- S is an end elevation, on4 a larger scale than Fig. 2 of one of the U shaped supplementary header members. Fig. 9 is a section on the line 9-'9 of Fig. 8. Fig. l0 is an elevation, and Fig. 11 a plan view of a device employed for connecting the ends of the superheating tubes inserted in a flue tube. Fig. 12 is an elevation, and Fig. 18 a plan view, of a tube spacing' device. Fig. 14 is a side elevation of a portion of a group of superheating tubes lemployed in one form of the invention. Fig. 15 is an end elevation'ofr the tubes shown in Fig. 14. Fig. 16 is a transverse section of the main steam header illustrating a valve arrangement 'which may be employed for connecting the saturated and superheated steam chambers under some conditions. Fig. 17 is a partial sectional elevation, taken similarly to Fig. 1, showing a modified arrangement of the smaller flue tubes.

In the formA of apparatus embodying the invention illustrated in the drawings, H represents the cylindrical wall and H an end wall of the boiler shell proper of a multitubular boiler of the locomotive type.

A and A represent the enlarged flue tubes receiving the superheater tubes and arianged in the form shown in two horizontal rows.

[t2 represents the main tlue tubeswhich are smaller in cross section than the tubes A and and A3 represents tubes which may be similar to the tubes A2 and are arranged between the two rows of tubes A and A.

K represents the steam pipe leading from the steam space of the boiler. In the smoke box the pipe K is bifureated, the branches E leading to the connections B3 at the ends et the main header B. The latter extends transversely to the i'iue tubes and is located between the two rows of tubes A and A.

The header B is formed with an upper' chamber B1 for saturated steam in communication at its ends with the pipes K and with a lower chamber B5 for saturated steam in communication at its ends with the pipes L through which the superheated y steam is conveyed to the engine cylinder or cylinders, As shown, the pipes L lead from the lower sides of the header end connections B3. The chambers B4 and B5 are separated by the division wall B8. The back wall B6 of .the header, that. facing the smoke box door, is Jformed with ports B9 and B91 communicating with the saturated and superhcated steam chambers B4 and B5 respec tively. These ports are arranged in two horizontal rows vand the ports B9 and B91 are disposed alternately in each row. The ports B9 in the lower row are connected with the chamber B11 by the curved passages B7 and the ports B91 in the upper row are connected with the chamber B5 by similar passages B7.

To obtain the desired uniformity' of flow and at the same time to economize in the weight of material employed in the header and the space occupied, the header is shaped to give a decreased width, measured parallel to the length of the iue tubes, of the .chambers B4 and B5 and a consequent decrease in `the area of those. chambers from the points B where the steam firstenters and finally leaves the header to the middle point B2 of the header.

To the back wall B" of the main header B is connected a plurality of U shaped members or supplemental headers C in two rows,

one row projecting upward and the other downward. Each leg of each member C is hollow and is provided in its front wall with an aperture C through which, when the U shaped members are secured in position. on

the back wall of the header, over the two rows of apertures B9 and B91 communication is established between one leg of each member C and the saturated steam chamber B'1 and between the other leg of each member C and the superheated steam chamber B5. The front .wall of the legs of each U shaped member'Q is provided with a plurality of apertures C2 for receiving the ends of a group of superheating tubes E. the back eeaoee wall ot the U shaped members has also a number of apertures coinciding with those in the frontwall, these apertures being closed by screw plugs C3.

Each U shaped member C is provided with an aperture C4 near the bottom ot' the U whereby it is secured-to the back wall of the vheader by a stud and nut C5, the apertures B10 in the back wall of the header being adapted to receive the various studs.

In veach of the enlarged lue tubes A and A of the boiler is placed a hollow horse shoe shaped member D having a plurality of apertures D in its back walls into which the ends remote from the headerof the tubes E of the corresponding group of superheating tubes are secured and placed in communication with each other.

The tubes E con-nected at one end to the two hollow legs of each U shaped member C, and at the other end to each other b the hollow end member D, form loo ed tubular connections between the le an each member C, the group of tubes connected to it and the corresponding member D form a superheating unit separately secured to the main header. The bodies of the tubes E of each unit are in alinement with the apertures D in the members D and consequently are disposed in cross section in the general form of'a horse shoe shaped archway, and the lugs of the corresponding auxiliary header C are so spaced apart as to provide a passageway in line with said archway through whichethe cleaning device may be inserted Ainto the corresponding line tube.

The apertures in the front wall of each of the U sliaped members C are not all in alinement with those of the corresponding horse shoe shaped members D, consequently some of the tubes have a slight set at E in that portion outside the flue tube A or A so as to bring them in line with the apertures C1 in the member C.A

Each group of superheating tubes E with the horse shoe shaped members D, when placed in the corresponding tlue tubes A or A leaves a space at the bottom of the liuc tube admitting of the flue tube as well as the superheating tubes being readily cleaned.

In order that the plurality of superheating tubes E .forming each group may be kept in position, a series of spacers in the form of horse shoe shaped pieces of plate F with apertures F corresponding to the pitch of the superheating tubes are placed over the tubes in suitable positions; these plates also serve the purpose of retarding and mixing the gases of combustion, thereby increasing the efliciency of the superheater as a whole.

In cases of one or more of the superheating tubes E of a unit failing the unit can be readily removed Aby disconnectin(r the nut en the stud C5 by which the member' C ot' the unit is secured to the header l. The complete unit comprising the U shaped member C, the group ot superheating tubes lil with the horse .shoe shaped members l) and horse shoe shape pieces ot plate lf can then be removed-to enable a blank plate to be secured to the header on the same stud over the two apertnresB9 and Bf" in the. back wall uncovered by the removal ot the member C thereby enabling` the engine to work as usual with a group of superheating tub@ out. of use. i Instead ot employing the end members l) the tubes .li ot each unitmay be connected together in pairs by inte gral curves connecting portions E2, as shown in Fig-sda and 15.

lYhile we hare described one header having U shaped members projecting beyond the top and bottom walls and a row ot tine tubes ofenlarged diameter situated beyond the top and bottom walls of the header it is obvious that. we may Vwithout departing from the scope of our invention employ more than one row ot' enlarged tlue tubes in such positions. le may also employ more than one header, in which ease they would be connected to each other in any suitable manner.

The port-ion of the superheater in the smoke box is inclosed in a easing G provided on -its under part with a damper G adapted to vary the proportion `ot drawn through the enlarged and ordinary flue tubes, covered by the casing, and the tubes ot' less diameter below the superheating casing whereby the degree ot' snperheat may be varied. The :trout cover plate G2 of the superheater is also hinged to enable it to be readily opened for cleaning and other purposes.

In order that the superheater may be etlicient in supplying the requisite quantity of steam when the capacity ot'- the groups ot` superheating tubes are temporarily reduced owing to one or more having been disconnected, or from other causes, we may place one or more valves over corresponding ports B1" in the partition wall B of the main header adapted to open to admit steam from the saturated into the super-heated steam chamber on the pressure in the latter falling below that `ot the former, as shown in Fig. l0. g

By the disposition ot a row or rows of enlarged due tubes A, A, on each side of a row or rows of ordinary or small tine tubes A3 we are enabled to use a header or headers of comparatively short depth, or depths, thus insuring as near as possible an even draft through the rows of the enlarged tine tubes as well as the ordinary or small tine tubes, the ends of which are inclosed by the casing. l.

In order that we may utilize the heating surface of the superheating tubes in the en` larged Hue tube A, A', to the best advantage we may reduce the diameter of theends of the ordinary or small flue tube A3 which are sandwiched between them,'as indicated in Fig. 17, so as to reduce their area and cause more gases to pass through the enlarged tine tubes A, The end members D and the spacers F serve also to retardand mix the gaseous products of combustion flowing through the` enlarged tine tubes thereby increasing the etiiciency oi the superheater as a whole. lv/loreoyer, the construction shown by permitting the use of a comparatively large number of superheating tubes in each enlarged tine tube thereby reduces the volume of the central core of the products of combustion passing' through the enlarged tlues and this adds to the etliciency ot' the superheating provisions as a whole, since the heat is not effectively abstracted from such a central core. A further advantage in the use of ordinary or small tubes sandwiched betweenv two or more rows ot' enlarged tine tubes is that the tube plates are not weakened to such an extent as when a number of rows .of Ienlarged tine tubes are arranged in consecutive rows.

By the disposition of a row or rows ot enlarged flue tubes on each side et' a row or rows of ordinary or small tine tubes we are.

obviously enabled to use a header or headers of comparatively .short depth or depths thus insuring as near as possible an even draft through the large flue tubes, as well as the ordinary or small flue tubes, the ends ofwhieh are inelosed by the casing.

By this construction'of superheater we can readily employ a relatively large number ofgsmall diameter superheating tubes, in each enlarged flue tube, thereby increasing the etiiciency as we reduce the area of the central core ofrsteam which is 'not super.

heated to an appreciable extent with superheating tubes of comparatively large diameter.

Having now described our invention, what we claim as new, and desire to secure by Letters Patent, is:

1. @he combination with a boiler provided -wit-h a plural-ity of enlarged iue tubes, of a superheater therefor comprising a main header extending transversely to said tine tubes at one end thereof and provided with a saturated steam chamber and with a su` 'perheated steam chamber, a series of hollow members in communication with one' of said chambers, a second series of hollow members in communication with the other of said chambers, 'said hollow members being detaehably connected to the wall of said header. most remote from the ends of said tubes and projecting beyond the. top and bottom walls ot said header with the memA bers of each series alternately disposed, and

superheating tubes extending some above tubes, at one end thereof, and provided with a saturated steam chamber and with a superheated steam chamber, a plurality of U shaped members detachably secured to the wall of said header most remote from the ends of said flue tubes and each having hollow legs, one of which is in communication with the saturated steam chamber, while the -other is in communication with the superheated steam chamber, and a group of superbe-ating tubes for each U shaped member which are connected at one end, some to one, and the others to the other, of the hollow legs ofthe member, andv which are connected to each other at their ends remote from said member to thereby form loo ed tubular connections between said ho low legs, the superheating tubes connectedto each U shaped member, all projecting into asingle corresponding flue tube.

3. The combination with a boiler provided with a plurality of enlarged lue tubes, of a superheater therefor, comprising a main header extending transversely to said flue tubes, at one end thereof, and provided with a saturated steam chamber and with a superheated steam chamber, and a plurality of units, one for each of said enlar ed tlue tubes and each comprising a pair o hollow members, in communication, one with one, and the other with the other, of the chambers in said header, and a group of tubes which are connected at one end, some to one, and the others to the other, of said hollow members, and at the other end are connected to each other to provide looped tubular connections between the two hollow memlwrs adapted to be insertedin a single coi responding enlarged flue tube.

4t. The combination with a boiler provided with a plurality of enlarged flue tubes, of a snperheatcr therefor comprising a main header extending transversely to said tine tubes, at one end thereof, and provided with a saturated steam chamber and with a superheated steam. 'chaniber, and a plurality of units separately connected to the header, vand each comprising a supplementary header detachably connected to the end wall of the main header most remote from said line tubes and having a pair of hollow legs, one

in communication with the one andthe other in communication with the other of the chambers in said header, and a group of tubes which arcconnected at one end, some to one and the others to the other of said hollow legs, and which are connected at their ends to each other to provide looped tubular connections between the two hollow legs adapted to be inserted in a corresponding enlarged iiue'tube.

The combination with a boiler provided with a plurality of enlarged tiue tubes, of a superheater therefor comprising a main header extending transversely to said flue tubes, at one end thereof, and formed with a flat and substantially vertical back wall and with elongated saturated and superheated steam chambers running lengthwise of the header and diminishing in width measured parallel to the length of the flue tubes from each end of the header toward the middle portion thereof, steam supply connections to the endsvof the saturated steam chamber and steam outlets from the ends of the superheated steam chamber and superheating tubes forming looped tubular connections between said chambers detachably connected to the back wall of the header at intervals along the length thereof.

(5. In aflue tube superheater the combina- 'tion with saturated steam and superheated s'team conduits, of one or more looped tubular connections rbetween said conduits, each comprising a group of tube portions adapted to be inserted in a boiler iiue tube and arranged in cross section in the form of a horse shoe shaped archway and hollow conf nections between said tribe portions and conduits, said hollow connections being spaced apart to provide a passage way in line with said archway through which a cleaning device may be passed into the tine tube receiving said tube portions. i

7 In a flue tube 'superhleateig the combination with saturated steam and superheated steam conduits of a group of tube portions adapted to be inserted in a boiler ue tube,

an end connection for the inserted ends of said tube portions in Lthe form of a hollow horse shoe shaped member having apertures in one end wall receiving the ends of said tube portions and hollow connections by whichsoine of said utube portions are connected with one and the remaining tube. portions lare connected with 'the other ot' said steam chambers, said hollow connections being spaced apart to provide a passage 1n line with said archway to permit a. cleaning device to be inserted in the tine tube receiving said tube portions.

S. ln a tlue 'tube superheater, thc combination with saturated steam and superheated steam conduits, of one or morelooped tubu- 'lar conne/tions between said conduits, each @espec to engage said tube portions at a distance from their inserted ends to hold them in the desired relative positions, hollow connections between said tube port-ions and conduits, said hollow connections being spaced apart to provide a passage way in line with said archway through which a cleaning device may be passed into the flue tube receiving said. tube portions.

9. In a flue tube superheater, the combination with saturated steam and superheated steam conduits of one or more looped tubularconnections between said conduits, each comprising a group ot tubes adapted to be inserted in a boiler iue tube and arranged in cross section in the form of a horse shoe shaped archway and a pair of hollow members connected one 'to one and the other to the other of said steam chambers7 the outer ends of said inserted tubes being connected some to one andthe remainder to the otherI .of said hollow members and the lat'ter being spaced apart to' provide appassageway in line with'said archway through which a cleaning device may be passed into the tiue tube in which said group of tubes are inserted.

10. 1n a flue tube superheater, the combination with a main steam header formed with saturated steam and superheated steam chambers, of a U shaped member connected to said header and formed with hollow legs, one in communication with the saturated steam and the other in communication with the superheated steam chambers and a group of tubes connected to said hollow legs and connected to each other to form looped tubular connections between said hollow legs, said group of tubes being adapted to be in- -ser'ted in a boiler flue tube and being. ar- -ranged in cross section in the torni ot a horse shoe shaped archway to permit ot cleaning devices to be passed into the tlue tube in which said group ot tubes may be inserted.

l1. In a iue tube super-heater, the combination of a main header provided with a saturated steam chamber and with a superheated steam chamber, ot a plurality of units separately connected to said headers and each comprising a pair ot' hollow mem bers, one in communication with one and the other in communication with the other ot said members, and a group ot' tubes adapted to be inserted in a boiler flue tube and having their inserted ends connected together and their other ends connected, some to one and the remainder to theother ot' said hollow members with the portions-ot the tubes inserted in the tine tube arranged in cross section in the form of a horse shoe shaped archway and with the ends of the tubes connected to thc hollow member arranged in two rows and the adjacent portions of some of the tubes correspondingly bent, said. hollow members being spaced apart to provide a passage in line with said` archway through which a cleaning device may be passed into flue. tubes surrounding said group of tubes.

12. The combination with a boiler provided with a plurality of enlarged flue tubes arranged at different levels, of superheating provisions comprising a main steam header extending transversely to said flue tubes and above some and below others thereof, said header being formed with a saturated steam and a superheated steam chamber and being formed in its baclr wall with a plurality of ports arranged in two horizontal rows, with alternate ports in each row communicating with one and the other ports communicating with the other'of said two chambers, a plurality of supplemental headers secured to said main" header in two rows, one row comprising' hollow legs projecting above the upper edge of the main header and the other hollow legs projecting below the lower edge of the header with the hollow legs in each row in communication, each with a corresponding port in the corresponding row of ports whereby each alternate 'leg is connected to one of said steam chambers and the intermediate legs are connected to the other steam chamber, and looped tubular connections connecting the hollowv legs in each row together in pairs, and each tubular connection entering a corresponding enlarged flue tube.

13. The combination, with aA boiler pro vided with a plurality of enlarged tlue tribes arranged in ltwo horizontal rows, of a plurality of smaller flue tubes arranged some between the two rows ot enlarged flue tubes and some below the lower row ot enlarged iiuc tubes, of.supcrheating provisions comprising a main header extending transverscly to 4the tlue tubes between the upper l and lower rows of enlarged Hue tubes, and formed with saturated steam and superheated steam chambers, and looped tubular connections secured to said header and inserted in the enlarged flue tubes of each row, and each tubular connection connecting the two chambers thereof and being composed ot a group of tubes inserted in a correspond ing one of said enlarged liuc tubes.

l-l-. The combination, with a boiler' provided with a plurality ot enlarged flue tubes arranged in two horizontal rows, and a4 plurality ot smaller tluc tubes arranged partly between and partly below the lower of said rows` ot supcrhtaiting provisions comprising a main steam header extending transversely to the flue tubes between the upper and lower rows or. enlarged llue tubes and tormed with saturated steam and superheated steam chambers and having formed in its back wall a plurality of ports a'rranged in two horizontal rows, each formed alternately of ports communicating with one and ports communicating with the other of said two chambers, a plurality of U shaped members secured to said header in two rowe7 one With 'the legs projecting above the upper edge of the header and the other With the legs projecting below the lower edge of the header, and each having its legs hollow and in communication one With a port running to one of said chambers and the other with a port running to the other of said chambers, and a looped tubular connection between the hollow legs of each U shaped ee'epee nected at one end, some to one and some lo the other of seid legs und connected :1t the other end to each other and adapted to be inserted in a corresponding enlarged flue tube.

GEORGE J. CHURCHWARD. GEORGE H. BURROVVS. CLIFFORD C. CHAMPENEY lVitnesses JAMES F. TANKDI,` E. J. FUSSELL. 

